Well bridge



March 16, 1954 PATTERSON 2,672,200

WELL BRIDGE 3 Sheets-Sheet 1 Filed March 1, 1950 INVENTOIIQ.

22247122035. PQZZEJ'EUIZ T. G. PATTERSON March 16, 1954 WELL BRIDGE 3Sheets-Sheet 2 INVEN TOR. 1 15012205151 Fazzez's'mz 2 H15 {FEE/V FiledMarch 1, 1950 March 16, 1954 T. G. PATTERSON WELL BRIDGE 5 Sheets-Sheet5 Filed March 1, 1950 INVENTOR. 51 5.222.425 flin [52:50.22 2 H15 EFF/WPatented Mar. 16, 1954 UNITED STATES PATENT OFFICE "WELL BRIDGE ThomasG.Patterson, Graham, Tex.

Application March 1, 1950, Serial No. 146,975

13 Claims. 1

This invention relates; to improvements in well bridges and moreparticularly to well bridges for positioning within the bore hole orcasing of a well, preparatory to the placing or in combination with theplacing of an explosive charge in the well to be detonated.

Various well bridges have been proposed heretofore, and while some ofthese have been reasonably satisfactory under certain conditions, theywere unsatisfactory under other conditions.

The present invention has been so designed as to meet all normalconditions confronting the placing of a bridge in the bore hole of awell, and furthermore, the invention meets certain other conditions andrequirements not found in bridges in use heretofore.

An object of this invention is to provide a well shooting bridge that iseasy to set, positive in action, andsafe to set and to remove should itbe prematurely located in the bore, hole of the well. i

Another object of this invention is to providea well shooting bridgethat may be seated either in theopen bore hole of a well, or within thecasing of the well.

A still further object of this invention is to provide a bridge whichmay be utilized to carry an explosive charge below thebridge while thebridge is being lowered into place.

Still another object of the invention is to pro- 1 vide a well shootingbridge'which has an uninipededcentral opening through a portion thereofvto permit the seating of an explosive charge within the interior or thebridge, such as a time bomb.

A still .further object of the invention is to provide a well shootingbridge having an expand- .able member secured thereto and surroundingsaid bridge to enable the placing of gravel or other medium aroundthelbridge so as to properly direct the force of the explosive whendetonated. Yet another object ofthe invention is to proelement thatsurrounds the bridge, and which i releasable band hasno projectionsthereon which extend beyond the outer periphery of said flexibleelement.

With til?above.ob-jects-in-mind and others that. i l-be ome pparent asthe descripti n-F ceeds, the invention will best be understood from thefollowing description, taken in conjunction with the accompanyingdrawings, which make up a specification of the same, in which:

Fig. l is a vertical sectional view through -;a bore hole of a well,showing the bridge in seated relation, with parts shown in elevation andwith parts broken away and shortened, and shown in phantom outline, tobring out the details of construction;

Fig. 2 is a fragmentary view of the lower portion of the well shootingbridge, showing the gripping dogs in retracted position;

Fig. 3 is a fragmentary view of the lower portion of the well shootingbridge, showing the surrounding flexible element or umbrella in closedposition, and showing the retaining U-pin in position to retain theumbrella in retracted position;

Fig. 4 is a fragmentary view of the upper portion of the well shootingbridge, taken substantially at right angles to Fig. 2;

Fig. 5 is a sectional view taken on the line 5-5 of Fig. 4, looking inthe direction indicated by the arrows;

Fig. 6 is a sectional view taken on the line 66 of Fig. 4, looking inthe direction indicated by the arrows;

Fig. 7 is a sectional view taken on the line 1-1 of Fig. 4, lookinginthe direction indicated by the arrows;

Fig. 8 is a perspective view of the flexible retaining band to retainthe umbrella or flexible element in closed condition during the loweringof the bridge into the well;

Fig. 9 is an elevational view of a modified form of the tool, with partsbroken away and shown in section, of the tool in suspended position;

Fig. 10 is a sectional view of the tool taken on the line l0--l0 of Fig.9, looking in the direction indicated by the arrows;

Fig. 11 is a fragmentary view of the lower portion of the tool, showinga further modification of the tool and Showing the umbrella in closedposition; with parts broken away and shown in section to bring out thedetails of construction;

Fig. 12 is a fragmentary view of the tool, similar to Fig. 11, butshowing the umbrella in released and open position, and with partsbroken away and shown in section to bring out the details ofconstruction; and

Fig. 13 is a fragmentary sectional view of the upper portion of theupper tubular body, showing an attaching hook in elevation attached tothe bail thereof.

With more detailed reference to the drawing, the numeral I designatesthe bore hole of a well in which a casing 2 may be positioned asdesired. A bridge structure, generally designated at 3, is adapted to belowered into the bore hole 5 by means of a line 4, which line 4 hasrelease hook mechanism ,5 ,on the lower end thereof adapted to en age abail 6. While a conventional form of hook or release mechanism is shown,any desired form of the same may be used.

The bail 6 is pivotally mounted at l, and may hinge to one sidereleased, as shown in dashed outline in Fig. 4.

In lowering the bridge into the bore hole of the well, the tubularelement 8 to which the bail 6 is pivoted, will support a pair of sidebars 9,, which side bars 9 are slidably fitted over a squared key memberif), and the side bars 8 are held in' place by a disc or washer which iswelded to the key member 10, as is best illustrated in Figs. 2 and 5.When in suspended condition, the upper end of slot 12 rests on the upperend of key member Ill. A pair of elliptical arms 13 protrude downwardlyalong the inner faces of side bars 9, and are fitted within a retain nglug [5, as will best be seen in Figs. 4 and 6, so upon relative movementof the tubular member 8 and the side members 9, the lug member it willcause outward and inward movement of the elliptical arms 13, which armsI3 carry wall engaging dogs IS. The wall engaging dogs it are pivotallymounted on modified elliptical arms l3, so that the dogs IG may eithergrip the inner wallet the well casing with teeth ll, or the points ismay project outward as indicated in dashed outline l5 to position thearms outward, and at the same 4 time cause the spring to yieldablyretain the upper end of the dog, so as to cause the points 1'8 toproject outwardly almost at right angles with respect to the sidebars 9.

It is preferably to have the points It of barbed construction, so as todig into the side walls of the bore hole of the well. The side bars '9-ex tend downwardly and have slots 29 near the respective lower endsthereof, in which is fitted a squared key member, which key 21 has adisc or washer 22 secured to the outer face thereof, so .as to retainthe side bars 9 intermediate the disc 22 and the bottom -cylindricalmember 23. The bottom cylinder member 23 has a pair of modifiedelliptical arms 24 hinged at 25 to the lower tubular member 23. Themodified elliptical arms 24 pass upward along and in contact relation toside bars 9, and through a staple 26 in closed relation, so uponrelative movement of lower tubular member 23 with respect to side arms9, the arms 24 will be caused to move outward and downward relative tolower tubular member 23, as shown in Figs. 1 and 2.

As the side bar 9 moves upward with respect to the lower tubular member23, the lower bar of staple 28 will contact the under surface of themodified elliptical arms 24 tocause the .arms to withdraw into thepositionas shown in Fig. 2. The modified ellipticalarms 24 each-carry awall engaging .member 21 which may be in the form of a toothed slipmember having upwardly pointing teeth inversely disposed with respect tothe teeth H of the dog l6.

In this manner the teeth 28 of slip 2! will be caused to engage the wallof the well or of the casing upon upward movement of the lower tubularmember 23 relative to side bars 9.

The lower tubular member extends downward to form a preferably conicalpoint .29, which is adapted to receive an explosive charge container, orif desired, the explosive may be placed directly therein. A flexibleelement, such as a cord or cable 30, may be provided and is adapted tobe secured to or above release element 5, to extend downwardly withinthe interior of upper tubular member 23, to a point near the top of aflexible umbrella element 3!, to engage a U-shaped pin 32. The U-shapedpin 32 projects through loops 33 formed on the inner ends of flexiblebar member 32. The bar 34 protrudes through an openingwithin theumbrella 31 and "the lower tubular member 123, so as .to protect theloops '33 and U-shaped pin 32 against mislocation because ofencountering obstructions within the bore hole of the well.

The cord or cable 30 has suflicient slack therein so as to not disengagethe U -shaped element 32, until after the release mechanism '5 hasreleased the bridge, generally designated by the numeral 3, at whichtime the cord 39 will cause the U-shaped pin 32 to be withdrawn "fromloops 23, which will permit the bar '34 to open and cause a spreadingaction of umbrella 31.

The purpose of the umbrella 3| is to form an obstruction in the wellwhich will enable gravel or other material to be :packedia'round thebridge to retain debris from dropping downward into the well, during thefixingor placing of the bridge preparatory to shooting the well withnitroglycerin, dynamite, or other explosive.

A hook 35 is attached to the lower end of a conical point'29 and has aguard bar 36 attached to the conical :point 29 for cooperation with thehook 35 to make possible the attachment "of an explosive container 31 bybail 6a, as will be seen from Fig. 1. In this manner, one or more shotshells maybe connected to the bridge by a bail which connects to thehook 35,'the manner of attachment being shown in Fig. 9. A time bomb ora-speeial detonating charge may be carried within the bridge, or seatedtherein after the bridge has been run in place, as indicated in Fig. 1.

The umbrella 31 preferably has stays 38, which are hinged at 39 .to thelower end of lower tubular member 23. In this manner the umbrella,generally designated "at 3|, will spread out to close the comparativelysmall bore hole, or'it may extend out to close a comparatively largebore hole.

Operation 'In the operation of the device, thebridge, generallydesignated at 3, is attached to a cable, or to a steel measuring line bymeans of a hook or unlatching mechanism 5, and is lowered into the wellto the proper depth. In event the lower end of the bridge strikes anobstruction which retards the downward descent thereof and allows theslips 2-1 to engage. The device may then be raised and again lowereduntil it reaches the proper depth. Whereupon, the container 31 willengage the bridge or the bottom of the well, and the point 29 of thelower tubular member 23 will seat within the top of the chargecontainer, which will cause the upper tubular member "8 to slidedownward Withresp'ect to the side-bars '9.- In so doing, the sidebars'will slide downward with re-- speot to the lower tubular member 23.As upper tubular member 8 slides downward with respect to the side bars9, the downwardly extending modified elliptical arms i3 will be causedto move outward, either to cause teeth I! to engage the inner walls ofthe casing 2, or the dogs l6 to project outward into the open bore hole,if the tool is being used in .an uncased well. The points l8, in thisevent, will engage within the strata. After the dogs 16 have moved intoposition, the slide bars 9 will continue to slide downward with respectto lower tubular member 23, and the upper bar of the staple will cause aspreading action of the modified elliptical arms 24 so as to causeengagement of the teeth 28, either with the inner wall of the casing 2,or with the wall of the bore hole, if the well is uncased.

The teeth 28 of the slips 2'! are upwardly seating, whereas the teeth Il of the dog 1 5 are down wardly seating. In this manner the unit isrestrained against upward movement exerted by pressure exerted belowtubular member 23 and is constrained against downward movement by the.downwardly seating teeth I! or the points id of the dog.

After the device is securely seated and secured against upward ordownward movement, the lowering line 4 is detached from the bail E by ahook or unlatching member 5, which usually unlatches after a requirednumber of pulls are given to the line 4, then the line 4 is moved up.After the line 4 moved up and the cord or cable 36 which is attached toU-container 32, is slipped out of loops 33, the cord or cable 38, whichis attached to the cable 4 of the U-container 32, permits a plurality oftorsion spring elements S, one

for each stay, to swing the respective stays 33 outward. to cause aflexible element or umbrella to close the bore hole of the well toprevent the downward movement of gravel therein, as this umbrella servesas a container to receive a gravel pack, preparatory to the detonatingof an explosive charge.

Although it has been pointed out that the device is used in connectionwith the explosive charge containers 31, it may also be used without theumbrella, for safety protection against gun after the detonation hastaken place. When used with a gun perforator, the gun perforator may belowered into the exact place desired, and the device operated tothoroughly secure the same in place in the well to prevent either upwardor downward movement of the gun perforator, in event an unexpected flowof oil or gas is en countered. The tool may also be used in connectionwith the treatment of the oil strata by utilizing the effect of theseating of the tool carrying the umbrella, within the bore of the well,so that gravel or other sealing material may be placed in and above theumbrella 38 which will prevent an upward surge of pressure due to thereaction of steam or chemicals which may be used in the treatment of thestrata, thereby holding the pressure below the umbrella to causepenetration of the chemical under pressure, into the earth formation inthe bore hole-of the well.

The forms. of the invention, asillustrated-in Figs. '9 and .10, showsubstantially the same .body

and slip structure, as. described above and Show in Figs. 1 to 8, but adifferent release mesh-a nismis provided for the umbrella. This form ofthe invention, is provided with an upper tubular body 5| and a lowertubular body 52, havin rea spective slip members 53 and 54, respectively0p eratively comiected thereto. The side bars 55, in which therespective slots 56 and 5! are formed. and which slots permit slidingaction of key members 58 and 59 respectively. The side bars extenddownward below slot 51 and is secured to a ring 60, which ring is spacedoutward from body 52 so as to form an engaging member for re-entranthook portions 6| of stays 62. The stays 62 are secured to the canvas orfibrous element 63 by clips 64 riveted or otherwise se cured to thecanvas 63. The lower end of the stays 62 may be hingeably connected tobody 52. in the same-manner as shown in Fig. 1. A torsion spring may beutilized, which is similar to the torsion spring S, shown in Fig. 1, tocause an outward movement of stays 62, when the dcvice is in releasedposition in the well.

The ring is somewhat conical or spherical in shape, with upwardly andoutwardly diverging walls to inter-engage beneath re-entrant hookportion 6| of stays 62. The stays 62 are so formed that the points 65are in close prox imity to the outer circumference of the lower bodymember 52, which prevents engagement with obstructions on the walls ofthe well, should it become necessary to lift the device upward todislodge from an obstruction within the well.

With the bodies 5! and 52 in suspended relation, the side bars 55 willcause the ring 60 to move upward under reentrant hook portions Bl, so asto support lower tubular member 52, and also to keep the umbrella,generally designated by the letter U, in collapsed condition during thedescent of the tool into the well, and until it is desired to releasethe umbrella for spread ing outward in the bore of the well.

Upon downward movement of the device an exposive charge 66 may besuspended by hook 6.! until the explosive container 66 seats on thebottom of the well or on a bridge, at which time the lower body portion52 will seat on the explosive container 66, which will cause theumbrella U to open, so that gravel or other hole closing material may belowered or dumped thereinto, but not allowed to pass there-beyond. Thusthe umbrella holds the gravel or other material as it is filled into thebore hole of the well, so that it is held in the. desired place todirect the force of the explosive charge downward and outward.

The. form of the invention as shown in Figs. 11 and 12, is somewhatsimilar to the form'shown in Figs. 9 and 10, except that the-lower bodyportion 12 provides for the side bars15 to extenddownward and attach toan annular ring that has upwardly and outwardly diverging sides, so whenengaged with the stays 82, the umbrella will be held inward until thelower portion of body l2 seats upon an obstruction such as a bridge orthe bottom of the well. The ring 80 will then move downwardpermitting-the stays, which are preferably of resilient construction, tospring outward, as indicated in Fig. 12. In the form of the invention asshown in Figs. 11 and 12, the umbrella may be collapsed upon upwardmovement of the side bars 15, and the compressor ring 39 attachedthereto.

1 Other-features Ofi17hiS"fOrm. or thev invention. asslshownin Fleeceto; 12, inclusive; have been treated in the form of the invention shownin Figs. 1 to 8, and it is believed that these features have beendescribed in such manner as to be clearly understood, both as toconstruction and manner of operation, as not to require furtherexplanation, and that they have been sufficiently covered in thedetailed description of the form of the invention as shown in Figs. 1 to8.

Having thus clearly shown and described the invention, what is claimedas new and desired to secure by Letters Patent is:

l. A bridge for use in a well comprising a pair of longitudinally spacedbodies, a bar having projections thereon which bar slidablyinterconnects said spaced bodies, pairs of arms each arm of which ispivotally connected at one end to each of said bodies, each of said armshaving its opposite end pivotally connected to a slip member, each pairof arms being engageable with said respective projections on said bar soupon relative movement between said bodies and said bar, saidprojections will cause relative movement between said slip members andsaid bodies so as to cause ngagement of said slip members with the wallof said well upon movement of said end of said stays, and holding meansfor said inverted umbrella on said bar, means connecting with saidholding means on said bar to disengage said inverted umbrella so as topermit said umbrella to open by resilient action of the stays thereof sosaid umbrella will form a receptacle intermediate the walls of said welland the lowermost of said bodies.

2., A bridge to be lowered into a well by means of a lowering line whichbridg comprises longitudinally spaced upper and lower tubular bodies,means on the upper of said bodies for attaching a lowering line, barsslidably interconnecting said spaced tubular bodies, a pair of armshingeably connected to each of said bodies, each of said arms having aslip member swing-ably connected thereto, pairs of guide members on eachof said bars and each pair of said guide members interengageable with apair or said arms, each pair of slip members being adapted to movelaterally upon relative movement between said bodies and said bars, anumbrella element comprising a sheet of flexible material and ribs whichribs are pivotally connected to said lowermost tubular body near thelower end thereof for outward swinging movement of the upper end of saidribs, spring means for urging the upper ends of said ribs outward andmeans for interconnecting said ribs and said flexible sheet of materialfor unitary movement thereof to form a receptacle between saidlower-most tubular .nected to the uppermost of said bodies for movingone of said bodies relative to the other of said bodies and for loweringsaid bridge into said well and for removing it therefrom, pairs of slipmembers, and linkage means for pivotally connecting a pair of said slipmembers to each of said bodies, said projections on said bar slidablyengaging said linkage, each of said pairs of slip members being movableoutward successively into contact relation with the wall of said well bythe relative movement of the upper of said bodies downwardly toward theother of said bodies on said bar when the movement of the lower-most ofsaid bodies is arrested, and each of said pairs of slip members beingmovable inward successively by the movement of the upper of said bodiesupwardly away from the other of said bodies on said bar.

4. A retrievable bridge for wells comprising a pair of tubular bodiesspaced from each other longitudinally and axially aligned, a pair ofbars interconnecting said longitudinaly spaced tubular bodies which barshave projections thereon, which bars are slidable relative to each ofsaid bodies, means connected to the upper-most of said bodies for movingsaid bodies relative to each other and for lowering said bridge intosaid well and for removing it therefrom, pairs of slip members, andlinkage means for pivotally connecting a pair of said slip members toeach of said bodies and passing outwardly in contact relation with saidprojections, each of said pairs of slip members being separably movableoutwardly into contact relation with the wall of said well by therespective movement of one of said bodies toward the other of saidbodies on said bars, and each of said pairs of slip members beingseparably movable inward by the relative movement of one of said bodiesaway from the other of said bodies on said bar.

5. A retrievable bridge for wells comprising a pair of tubular bodiesspaced from each other longitudinally, a pair of bars interconnectingsaid longitudinally spaced bodies, which bars are slidable relative toeach of said bodies, means connected to one of said bodies for movingone of said bodies relative to the other of said bodies and for loweringsaid bridge into said well and removing it therefrom, slip members,pairs of arms hingeably connected to each of said tubular bodies andeach of said arms having one of said slip members pivotally attachedthereto near the outer end thereof, means slidably connecting each ofsaid bars with each of said arms so upon relative movement between saidbars and said arms in one direction, said slip members will be caused tomove outward, and upon movement of said bars with respect to said armsin the opposite direction said slip members will be caused to moveinward.

6. A bridge for lowering into a well by means of a pull line, whichbridge comprises a pair of longitudinally spaced tubular bodies, a pairof bars slidably interconnecting said spaced tubular bodies, a pair ofmodified elliptical arms hingeably connected to the lower end of theuppermost of said longitudinally spaced, tubular bodies and another pairof modified elliptical arms hingeably connected to the upper end of thelower-most of said bodies, slip members, each of said arms carrying oneof said slip members, means forming a sliding connection between each ofsaid arms and said pair of bars so as to spread said arms outward uponthe relative downward movement of said bar with respect to the lowermostof said bodies and by downward movement of the upper-most of said bodiesrelative to said bar, and; means connected to the upper-most :of "saidtubuia'r: bodies iior lowering said bridge into said: well andfior'm'oving said bodies and said bar relative to each other.

l. A- 'retrievaiblebridge for wells: comprising a pair of tubular bodiesspaced from each other longitudinally, a bar interconnecting saidlongitudinally spaced bodies and having projections thereon, which baris slidable relative to each of said bodies:,-moans connected to theupper-most of said bodies :for'rmoving "said. bodies relative toeach-other and for: lowering. said bridge into "said Well removing ittherefrom, pairs or slip members, and linkage means for piyotally"conmeeting 'apatr ot said clip members to" each of said bodies-whichlinkage meanspass outward in contact relation with-said projections;ea-ch pair 'of :said slipmembers being movable outward :sucoe'ssi velyinto contact relation with the wall of said well by relative inovtmentof. the upper most of said bodies toward the other of said bodies onsaid bar when the movement of the lower most of said bodies is arrested,and each of said pairs of slip members being movable inward by themovement of theuppermost of said bodies away from the other of saidbodies on said bar.

8. A bridge for wells which bridge is adapted toi'be set by a loweringline, said bridge comprisa pair of longitudinally spaced bodies, a barslidably "interconnecting said bodies and having projections thereon,pairs of slip members, linkage means hingeably connecting a pair of saidslips with each of said bodies, said projections on said bar slidablyinterengaging said linkage, each pair of said slips being movableoutward for engagement with the wall of said well by relative movementbetween said bodies and said bar in one direction and inwardly out ofengagement with the wall of said well when moved in the oppositedirection, the lower-most of said bodies having resilient stays securednear the lower end thereof which stays extend upwardly and outwardlywhen in open position, a covering surrounding said lower-most body andsecured thereto near the lower end thereof and to said stays to form aninverted umbrella, a ring surrounding said lower-most body near theupper end thereof and interengaging said stays when in one position tohold said umbrella in collapsed condition, means interconnecting saidlowering line and said ring for releasing saidring from said stays, anda releasable hook means on said lowering line connected to theupper-most of said bodies for moving said bridge in said .well.

9. A bridge for wells which bridge is adapted to be set by a loweringline, said bridge comprising a pair of longitudinally spaced bodies, abar slidably interconnecting said bodies and having projections thereon,pairs of slip members, linkage means hingeably connecting a pair ofslips with each of said bodies, said projections on said bar slidablyinterengaging said linkage, each pair of said slips being movableoutward for engagement with the wall of said well by relative movementbetween said bodies and said bar in one direction and inwardly out ofengagement with the wall of said well when moved in the oppositedirection, the lower-most of said bodies having resilient stays securednear the lower end thereof which stays extend upwardly and outwardlywhen in open position, a covering surrounding said lower-most body andsecured thereto near the lower end thereof and to said stays to form aninverted umbrella, a re-entrant hook on the upper end of each of saidstays, a ring iii) surroundingsa-id lower-most body near the upper endthereof and attached to said slidable bar and movable therewith, saidring: being in engagement with said re-entrant hooks when in. itsuppermost position, and being disengaged .irom said i e-entrant bookswhen in its lowermost position so as to release said umbrella stays andsaid :umbrella, means interconnecting with said lowering line and withsaid ring for releasing sari-during from'. said stays, and a releasable.hook means on said lower-ing line connected to 'said upper-most ofsaidbodies for moving said bridge in said well,

1-0. (A bridge for wells which. bridge is adapted to be set by alowering line, said bridge comprising a. pair of longitudinally spacedbodies, a bar slidably interconnecting said bodies and havingprotections thereon, pairs of slip members, linkage means hi-ngeablyconnecting .a pair of said slips with each of said bodies, saidprojections on said bar slidably interengaging said linkage, each pairof said slips being movable outward for engagement with the wall of saidwell by relative movement between said bodies and said bar in onedirection and inwardly out of engagement with the wall of said well whenmoved in the opposite direction, the lower-most of :said bodies having.resilientstays secured near the lower 'end thereof which stays extendupwardly and outwardly when .in open position, a covering:surroundingsaidllower-most body and securedthere- .to near the lowerend thereof and to said stays to form an inverted umbrella, a slitformed in said umbrella near the lower-most part thereof which slitreceives said slidable bar therethrough, a ring having its inner sidediverging upwardly and outwardly and said ring being connected to saidslidable bar and positioned below said umbrella and said stays so saidring will wedgingly compress said stays in collapsed condition when saidring is in its upper position, but which ring will permit outwardspreading of said umbrella and said stays when said ring is in its lowerposition, and releasable hook means on said lowering line connected tothe upper-most of said bodies for moving said bridge in said well.

11. A bridge to be lowered into a well by means of a lowering line, saidbridge comprising longitudinally spaced upper and lower tubular bodies,means on the upper of said bodies for attaching said lowering line, apair of bars slidably interconnecting said spaced tubular bodies andhaving projections thereon, pairs of slip members, linkage meanshingeably connecting a pair of said slip members with each of saidbodies, said projections on said bars slidably interengaging saidlinkage, each pair of said slip members being movable outward forengagement with the wall of said well by relative movement between saidtubular bodies toward each other, said lowermost tubular body beingclosed at its lower end to form a seat, an expansible umbrella membersecured to the lower end of said lower-most tubular body and extendingupwardly therearound, means coupled with said lowering line. forreleasing the upper end of said umbrella member so said umbrella memberwill open outwardly at its upper end to form a receptacle between saidlower-most tubular body and the wall of said well.

12. A bridge to be lowered into a well by means of a lowering line,which bridge comprises longitudinally spaced, upper and lower tubularbodies, means on the upper-most of said bodies for attaching a loweringline, bars slidably interconnecting said longitudinally spaced tubular 1l bodies and having projections thereon, pairs of slip members, linkagemeans hingeably connecting a pair of said slips with each of saidbodies, said projections on said bars slidably interconnecting saidlinkage, each pair of said slip members being movable for engagementwith the wall of said Well by relative movement between said bodiestoward each other on said bars, said lowermost tubular body being closedat its lower end to form a seat, an umbrella element comprising a sheetof flexible material and ribs, which ribs are pivotally secured to thelower end of said lower-most tubular body and extending upwardtherearound, a band surrounding the upper portion of said ribs, andmeans for coupling said band to said lowering line for selectivelyreleasing said band from said ribs so the upper end of said umbrellaelement will expand outwardly to form a receptacle between saidlower-most tubular body and the wall of said well.

13. A bridge to be lowered into a well by means of a lowering line,which bridge comprises longitudinally spaced, upper and lower tubularbodies, means on the upper-most of said bodies for attaching a loweringline thereto, a pair of bars slldably interconnecting saidlongitudinally spaced, tubular bodies and having projections thereon,pairs of slip members, linkage means hingeably connecting a pair of saidslips with each of said bodies, said projections on said bars slidablyinterengaging said linkage, each pair of said slip members being movablefor engagement 12 with the wall of said Well by relative movementbetween said bodies toward each other on said pair of bars, saidlower-most tubular body being closed at its lower end to form a seat, anumbrella element comprising a sheet of flexible material and ribs, whichribs are pivotally secured near the lower end of said lower-most tubularbody for outward swinging movement of the upper ends of said ribs andflexible sheet material, a flexible band surrounding the upper portionon said ribs, a loop formed on each end of said band, which loopsprotrude into said lower-most tubular body, a U-shaped connectorattachably fitted within said loops for normally retaining said band ina fixed relation around said ribs, and means connected to said U-shapedconnector and said lowering line for selectively releasing said bandfrom said ribs to cause the spreading of said umbrella element so as toform a receptacle between said lower-most tubular body and the wall ofsaid well.

THOMAS G. PATTERSON.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,497,629 Baker June 10, 1924 2,141,030 Clark Dec. 20, 19382,225,143 Baker et a1. Dec. 17, 1940 2,253,224 Bleakley Aug. 19, 1941

